This invention relates to a valve arrangement comprising a distributor housing containing a distributor duct, an inlet duct leading into the distributor duct and at least two outlet ducts leading out of the distributor duct, and also containing valves associated with each respective outlet duct and which define the flow cross-section for a medium flowing through the inlet duct and distributor duct into the respective outlet ducts.
Schnaus et al., U.S. Pat. No. 5,269,348 discloses a valve arrangement of this type which comprises an inlet duct and at least two outlet ducts. A valve is associated with each outlet duct in order to distribute the medium fed through the inlet duct as needed to the outlet duct or ducts. In particular, this valve arrangement is used for a viscous medium, such as a polymer melt, in order to facilitate distribution to extruders, spinning devices or the like connected to the outlet ducts. This known valve arrangement comprises a central distributor housing with the above-mentioned ducts and the valves mounted on the housing. Each valve comprises a valve body which can be axially moved like a piston and which is arranged essentially radially with respect to the central distributor housing, whereby the mushroom-shaped valve body can also be moved back and forth in the above-mentioned radial direction. The drive for moving the valve body must be constructed to be relatively large since the pressure of the medium acts upon the valve body to its full extent. Thus, this valve arrangement has comparatively large dimensions. Special measures are required in order to avoid dead spaces in which portions of the medium may be trapped. In principle, the valve body therefore has a mushroom-shaped construction, and the medium flows around the valve body both when the valve is closed as well as when it is opened. Such a construction involves considerable additional expense.
German Patent No. DE 4,027,622 discloses a regulating flap valve which comprises a housing and a duct for the flowing medium. A flap disk is rotatably disposed on a shaft in the housing, the flap disk being integrated into the shaft and being situated with its contour inside the shaft. The flap disk is arranged in a central area of the duct, which area has a rectangular, especially a square, cross-sectional surface.
Austrian Patent Document No. AT 218,808 discloses a valve arrangement for pressure control lines of flow media, in which case several regulating flaps are provided, each of which is associated with a respective outlet duct. In the center of a distributor housing, a common cam plate is provided for actuating the individual regulating flaps. Each regulating flap is pivotably arranged laterally of the mouth of the respective outlet duct leading into the distributor duct and contains a projection which can be engaged by the cam plate in order to open the regulating flap. This valve arrangement contains dead spaces, primarily in the area of the bearings of the individual regulating flaps, in which a viscous medium, such as a polymer melt, may become trapped. Separate and mutually independent actuation of the individual regulating flaps by means of the central cam plate is not possible.
Finally, German Patent No. DE 169,268 discloses a three-way valve which has two outlet ducts, to each of which a respective regulating flap is assigned. The outlet ducts have a circular cross-section and the regulating flaps can be swivelled about a common axis of rotation. There is no distributor duct, and the regulating flaps open by swiveling into the end region of the inlet duct.
Despite the efforts of the prior art, there has remained a need for an improved valve arrangement of the aforedescribed type.